Combined inductance coil and switch



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28s J. M. OEREEN m9739572 'COMBINED INDUCTANCE COIL AND SWITCH Filed June 22. 1933 2 Sheets-Sheet 2 Patented Aug. 28, 1934 A"PATENT OFFICE COLIBINED INDUCTANCE' COIL AND SWITCH John M. o'rien, wat Winfield, N. Y., signor of one-hau to Lona B. semi, wat Winfield,

Application June 22, 1933,*Serial No. 677,145

13 Claims.

inductance coil and switch and seeks, among other objects, to provide a device of this character which will be of such construction that rotation of the coil form employed will serve selectively to engage contacts for varying the inductance of a coil wound upon said form.

A further object of the invention is to provide an inductance coil and switch employing a series of circumferentially disposed contacts and means engageable with the contacts whereby positive connection may be effected so that there will be a minimum amount of losses.

A further object of the invention is to provide a combined inductance coil and switch wherein the inductance of said coil may be varied with the utmost facility so that a single device may be employed for covering a number of different bands of frequencies.

A still further object of the invention is to provide a combined inductance coil and switch which will be of rugged construction and which will be capable of use over long periods of time without attention.

And a still further object of the invention is to provide a device of this character which will permit the use of short connecting wires with consequent lowering of losses which would otherwise be caused by high capacity leads.

It is believed that a reading of the following description will disclose other and incidental objects which have not been mentioned hereinbefore.

My invention is illustrated in the accompanying drawings wherein, Figure 1 is a side elevation of my complete combined inductance coil and switch, A

Figure 2 is a vertical sectional view taken on the line 2 2 of Figure 1 and looking in the direction indicated by the arrows,

Figure 3 is a fragmentary vertical sectional view showing the coil form with coils wound thereon and showing how connections are made to the contacts and contact strips employed,

Figure 4 is a horizontal sectional view taken on the line 4 4 of Figure 2 and looking in the direction indicated by the arrows,

Figure 5 is a horizontal sectional View taken on the line 5 5 of Figure 2,

Figure 6 is a diagrammatic view the inductance coil properly connected to the contacts and contact strips,

Figure '7 is an enlarged fragmentary vertical sectional view showing a slightly modified form of my invention,

This invention relates to an improved combined Figure 8 is an enlarged fragmentary vertical sectional view of a still further modification of my invention,

Figure 9 is an enlarged fragmentary vertical sectional view showing another modified form of 6o my invention,

Figure 10 is an enlarged fragmentary vertical sectional view showing another modification,

Figure 11 is an enlarged fragmentary vertical sectional view showing a still further modication, and

Figure 12 is a horizontal sectional view taken on the line 12-12 of Figure 11 and looking in the direction indicated by the arrows.

Referring now more particularly to the drawings wherein like numerals of reference designate like parts throughout the several views, the numeral 1 indicates a c'oil form which is formed of Bakelite, or other suitable material having extremely high insulating value. The coil form is, as shown, circular but, if desired, radially extending ribs may be formed integrally with the coil form, or it may be formed with a hexagonal outer surface, it being understood that the'inner surface is to be circular at the points where the hereinafter described contacts are located. Mounted in the coil form l, near its lower end and extending throughout the major portion of the interior of said form, is a preferably Bakelite block 2, which block is secured in place by means of screws 3 extending through the wall of the form 1. If desired, the block 2 may be molded integrally. with the coil form and the contacts and wires hereinafter described may be molded in place at the same time. As best seen in Figure 4 of the drawings, the block is substantially square in shape, but is provided with arcuate corners to receive the screws 3. As will be observed, the straight edges of the block 2 extend in chordal relation to the arcuate inner surface of the form so that a small space will be provided between said edges and said arcuate surface.

Arranged circumferentially of the coil form 1, near its lower end, is a series of alined spaced contacts 4, and mounted on the interior of the coil form, substantially diarnetrically of certain of the contacts 4, are oblong contact strips 5 and 6. Wound about the coil form 1, near its upper end, is a preferably relatively small inductance coil 'Z and, as best seen in Figure 2 of the drawings, the inductance coil is tapped, and leads 8 are led therefrom interiorly of the coil form downwardly past the block 2 through the space defined between the arcuate inner surface of (iii the coil form and the straight edge of the block and are soldered or otherwise secured to certain of the contacts 4. The coil 7 may be a primary coil. a plate coil, or may be connected in any desired circuit arrangement, it being common practice to utilize a relatively small inductance coil, like the coil 7, as a plate coil, or the primary of a radio frequency transformer in a multi-wave receiving set. It should be understood, however, that the size of the coil is not material as regards the present invention. 'I'he lower, or lament, end of the coil 7 is connected by a lead 9 to the strip 5. Wound upon the coil form 1 below the inductance coil '7 and preferably in spaced and inductive relation thereto, is a relatively large inductance coil 10. The inductance coil 10 is usually employed as a grid coil, or as a secondary of a radio frequency transformer. Leading from the coil 10 within the form 1 to the remainder of the contacts 4 are leads 11, and leading from .one end of the coil 10 is a connecting wire 12 which is connected with the contact strip 6.

Rotatably connected with the form 1 is a base 13 which is formed of Bakelite, hard rubber, or any other suitable insulating material. As best seen in Figure 2 of the drawings, the base 13 is of a diameter slightly less than the diameter of the coil form 1. The base is provided with an upper portion 14 which is secured to said base by means of screws 15 extending from said upper portion into said base. The upper portion 14 is reduced in diameter with respect to the base 13 to denne a reduced side face 14 for said upper portion. Extending axially of the base 13 and through the upper portion 14 thereof and upwardly is a connecting screw 16 which is threaded at its upper end. A spacing nut 17 is screwed on said connecting screw and closely abuts the upper surface of the upper portion 14. The spacing screw provides additional means for clamping the upper portion 14 to the base 13. Washers 18 are carried on the connecting bolt and overlie the nut 17, the upper end of said bolt extending axially of the block 2 for rotatably connecting the base and upper portion with the coil form. Overlying the upper surface of the block 2 and carried on the bolt 16 are washy ers 19. Screwed on the upper end of the bolt 16 and overhanging the washer is a locking nut 20. It will be seen that the bolt 16 eiectually rotatably connects the base and upper portion with the coil form 1 so that the coil form may be rotated independently of the base and upper portion. Carried by the base 13 are a plurality of depending prongs 21 which are adapted for removable engagement with a socket of the type commonly employed for mounting vacuum tubes. In the present instance, I have shown ve prongs and the use thereof would necessitate the employment of a socket having ve prong-receiving openings. It should be understood that, while in the present instance I have shown the base as being provided with ve prongs, any suitable number of prongs may be employed, depending upon the circuit in which the coils are to be connected and also the number coils woundA upon the coil form. It is well known, in this connection, that sockets having six and seven prongreceiving openings are now in common use. The base may, if desired, be molded from a single piece of material.

Connected with the base 13 and extending upwardly into the coil form and-into selective engagement with certain of the contacts .and connecting strips are switch blades 22. As will be responding opposite ends extending between the upper portion 14 and the base 13, said corresponding opposite ends being soldered, or otherwise secured to the inner ends of the prongs 21. Screws 24 extend through the switch blades and into the base 13. The upper end portions of the switch blades are preferably slightly bowed longitudinally so that a rounded surface will be, presented toward the contacts and contact strips. Danger of locking the blades between the several contacts is thereby prevented.

In use, after the coil has been plugged into a socket, and the set has been operated on a given band of frequencies, it may be desired to change the responsiveness of the receiving set to a different band of frequencies. With my device it is only necessary to rotate the coil form 1 with respect to the base 13 for engaging certain of the switch blades with a different pair of contacts, the other of said switch bladesrbeing slidable on the strips 5 and 6 for maintaining a constant connection therewith. It should, therefore, be understood that the necessity for removing the coils from the sockets and placing new coils therein, with attendant bother, will be eliminated. 'I'his is particularly advantageous when the sockets are located in places which are not easily accessible within the radio. The switch blades are formed of such material that they will engage the contacts under a slight tension -so that a positive contact will be effected. Loose connection, with consequent great loss in eiciency will therefore be practically eliminated. A

Referring now more particularly to' a modification of my invention, as disclosed in Figure '7 of the drawings, the numeral 25 indicates a coil form which is of similar construction to the coil form 1. The coil form is provided withcontacts 26 arranged in an annular spaced series. The numeral 2'7 indicates a base of insulating material which is rotatably mounted with respect to the coil form by means of a shaft 28 extending axially of such base and axially of the coil form, the upper end of said shaft extending through a wall 29 formed integrally of the coil form 25. A nut 30 retains the coil form in rotatable relation with respect to the base. The shaft is adapted to extend downwardly so that it may be rotated by a pulley and belt, a chain, or some other suitable means, thuspermitting the shifting of the coil form without the need of raising the lid and grasping the form itself. In this embodiment, the coil form will be mounted permanently in the set. Carried by the base, near its upper end, is a cylindrical plunger housing 31 which is disposed radially of the base 27 and extends throughout the major portion of the radius of said base. Slidable in the plunger housing is a plunger 32 and carried` in said housing and normally urging the plunger selectively against the contacts 26 is a coil spring 33. A prong 34, is connected with the housing and is adapted for insertion within a socket. It is to be understood that a plunger, plunger housing and spring are to be employed in connection with each of the prongs and the number are to be determined by the socket to be employed and the circuit to be utilized, as in the preferred form of the invention.

A further modification of my invention is shown in Figure 8 wherein the numeral 35 indicates a coil form which is provided with a wall 36. The wall 36 is disposed a slight distance above the lower end of the coil form to define a lower rim 37. Mounted on the rim 37 are preferably two annular series of spaced contacts 38 and 39. Rotatably connected with the coil form is a base 40 of insulating material which carries the prongs 41. As will be observed, the base is reduced in diameter toward its upper. end and said end is rotatably secured to the coil form 35 by means of a bolt 42 extending axially of said base and axially of the wall 36. A nut 43 is screwed 0n the upper end of said bolt for limiting the base against upward movement. Carried by the base .and connected to certain of the prongs 41 is a relatively long spring contact arm 44 which is adapted for selective engagement with the contacts 38, while carried on the base and electrically connected with a prong 41 is a relatively short spring contact arm 45 which is adapted for selective engagement with the contacts 39. Screws 46, extending radially and inwardly, serve to clamp the contact arms 44 and 45 to the base and also serve to electrically connect said prongs 41 with said spring arms. The spring arms 44 and 45 serve to connect portions of inductance which are connected to the conl tacts by means of leads, as in the preferred form of the invention, it being only necessary to rotate the coil form to connect certain of the contacts with the spring arms and it is, of course, to be understood that a spring arm is employed for each of the prongs.

A further modication of my invention is shown in Figure 9 wherein the numeral 47 indicates the coil form upon which the usual inductance coils are wound, the coil form being provided at its lower end with a radial flange 48 and also provided with an inner wa1l49 disposed near its lower end. Contacts 50 are carried on the radial flange 48 in an annular series. Rotatably connected with the coil form 47 is a base 51, the lower portion of which is of a diameter equal to the diameter of the radial ange 48, the upper portion being reduced, as indicated at 52 to t freely within the coil form 47, in close spaced relation to the lower surface of the wall 49. Rotatably connecting the base with the coil form and extending axially of said base and axially of the coil form 49 is a bolt 53 which is provided with a nut 54 at its upper end. A washer 55 is disposed between the lower surface of the wall 49 and the upper surface of the base 51 for effectually spacing said base from said wall. Mounted in the base 51, near its outer end and disposed vertically therein, is a plunger housing 56 and slidable in said housing and disposed selectively to engage the contacts 50 is a plunger 57 which is normally urged upwardly by means of a spring 58. Carried by the base are prongs 59 which are electrically connected to the plunger housing by means of a lateral portion 60. In this form of my invention it is only necessary to rotate the coil form with respect to the base for selectivelyv engaging the plunger, or plurality of plungers, one being utilized for each prong, with certain of the contacts for varying the inductance on the coil form.

The further modification of my invention,

shown in Figure 10 of the drawings, comprises a coil form 61 having a wall 62 disposed above the lower edge of said form to denne a lower portion 63. A series of contacts 64 are arranged at the lower edge of said coil form. Rotatably connected with the coil form is a base which comprises a central portion 65 and an outer portion 66 which denes an annular groove 67 between said central portion and said outer portion. The lower portion of the coil form is adapted freely to rotate within the groove 67 and its outer surface is in relatively close spaced relation to the inner surface of the outer portion 66. Carried in the outer portion 66, near its upper extremity and opening inwardly, is a plunger housing 68, and carried in said plunger housing is a plunger 69 which is normally urged inwardly for selective engagement with the contacts 64 by means of a spring 70. It is to be understood that a plunger, housing and spring are to be employed for each of the prongs carried by the base, such a prong being shown at 71 and being connected with the housing by means of a lead 72. The prongs, as in the preferred construction, are intended to be inserted into a socket for mounting the coil. It should be understood that rotation of the coil form will selectively engage the plunger with the contacts for varying the inductance of the coils carried on the coil form and rotation of the coil form is done in the same manner as that of the preferred form.

The further modification of my invention, as shown in Figures 11 and 12 of the drawings, utilizes a coil form 73 which is closed at its lower end by means of a bottom wall 74. Formed on the bottom wall 74, interiorly of the form 73, is an upstanding boss 75. The coil form is to have inductance coils of suitable size wound thereon. Carried on the coil form in an annular spaced series above the bottom wall and in a plane horizontal to the plane of the bottom wall are annular groups of contacts 76. Carried by the coil form and depending therefrom are screws 77 and connected to said prongs, inwardly thereof, are upwardly projecting spring contact arms '18. Mounted within the coil form 73, above the boss 75, is a cam contact operating disk 79 which is formed with cam faces 80 at its circumferential edge, said cam faces being adapted selectively to confront certain of the arms 78. Rotatably mounting the disk within the form and above the boss is a shaft 8l, the shaft being connected with the disk by means of nuts 82 and 83 disposed at each side of said disk. The shaft 81 is adapted to project downwardly axially of the coil form, and carried on the lower end are bevel gears 84 which are adapted for driving the shaft and rotating the disk, so that when it is desired to change the value of the inductance of the coil are shifted forwardly for contacting selectivelyV certain of the contacts 76. It will be seen' that the inductance may be thereby eflectually changed. 'Ihe screws 77 may be secured' permanently to a sub-panel and connections-made thereto.

In the modification of `my invention, it is believed that it will be understood that the general spirit of the invention, as shown in the preferred form, has been embodied throughout, such mcdications contemplating slight changes in construction which I have employed to meet certain conditions.

It should be understood that the plug-in-feature may, or may not, be used in either the preferred or modied forms o! the invention, the use of said feature to be governed by specific conditions.

It is believed that a reading of the foregoing description will disclose that I have provided a device of this character lwhich will be highly efcient in use and simple in construction.

Having thus described my invention, I claim:

l. A combined inductance coil and switch including a coil form, inductance coils thereon, contacts carried on the coil form, means axially rotatable with respect to the coil form for selectively engaging the contacts whereby variation of the inductance of the coils on the form may be effected, means for mounting the coil form within a radio set and being fixed to said means, and means electrically connecting the coils with the contacts.

2. A combined inductance coil and switch including a coil form, inductance coils thereon, contacts on the coil form, means connecting said contacts with said coils, contact arms, means axially rotatable for shifting the contact arms and selectively engaging certain of the contacts whereby variation of the inductance of the coils may be effected, and means mounting the device in a radio set and i'lxed to said second mentioned means.

3. A device of the class described including a coil form, inductance coils thereon, means removably mounting said coil form within a radio s'et, contacts carried by the coil form, means electrically connecting the coils with the contacts, and means selectively engageable with the contacts for varying the inductance of the coils on the form, said rst mentioned means being mounted on said second mentioned means.

4..A device of the class described including a coil form, inductance coils thereon, contacts carried by the coil form, means electrically connecting the coils with the contacts a base rotatably mounted on the coil form, switch blades carried by the base and selectively engageable with the contacts, and prongs carried by the base and removably engageable in a socket whereby the device may be removably mounted within a radio set, selective engagement of the contacts by the switch blades as the form is rotated relative to the base serving to change inductance of the coils on the form.

5. lA device of the class described including a coil form, inductance coils thereon, a block carried within the coil form, contacts carried bythe coil form and arranged in spaced circumferential series, leads connecting certain of the contacts with portions of the inductance coils, a base rotatable with respect to the coil form, means rotatably connecting the base with the block, prongs carried by the base, switch blades carried by the base and selectively engageable with certain of the contacts, and means electrically connecting the switch blades with the prongs, said prongs being adapted to removably mount the device in a radio set and said coil form being adapted for rotation with respect to the base whereby selective engagement of the switch blades with the contacts and consequent variation of the inductance of the coils may be effected.

6. A device of the class described including a coil form, inductance coils mounted thereon, contacts mounted on the coil form, contact strips mounted on the coil form, leads connecting portions of the coils with the contacts, leads connecting the electrical ends of the coils with the contact strips, a base, an upper portion thereon, means rotatably connecting the base and upper portion with the coil form, prongs carried by the base, and switch blades carried by the base and electrically connected with the prongs, said coil form being rotatable with respect to the base for selectively engaging the switch blades with the contacts and strips whereby variation of the inductance may be eiected.

7. A device of the class described including a coil form, a block carried therein, inductance coils wound about the form, contacts carried by the l form, leads connecting portions of the coils to said contacts, a base rotatably connected with the coil form, an upper portion secured to said base and rotatable freely within the lower end portion of said coil form, means connecting the base and upper portion with the block, means securing the upper portions to the base, switch blades carried by the base and projecting upwardly, said switch blades being adapted for selective engagement with the contacts, and prongs carried by the base and electrically connected with the switch blades, said prongs removably mounting the device in a radio set, the coil form being rotatable about the base for selectively engaging the switch blades with certain of the contacts and varying the inductance of the coils on the form.

8. A devicerof the class described including a coil form having a wall, an inductance coil on the coil form, contacts arranged on the coil form, means electrically connecting the coil with the contacts, a base rotatably connected with the c'oil form, means connecting said base with the wall, a prong carried by the base, a plunger housing carried by the base and connected with the prong, a plunger carried by said housing, and a spring carried by said housing and adapted for urging the plunger forwardly into selective engagement with the contacts for varying the inductance of the coil on said coil form as said form is rotated about said base.

9. A device of the class described including a coil form having a wall and a lower portion, an inductance coil wound on the form, spaced series of contacts carried'on said lower portion, means electrically connecting the coil with the contacts, a base rotatably connected with the coil form, prongs carried by the base and adapted for removably mounting the device in a radio set, a relatively long` spring arm carried by the bas and selectively engageable with one of the series of contacts, a relatively short spring arm carried by the base and selectively engageable with other series of the contacts, and means connecting the arms to the base and electrically connecting said arms to the prongs whereby rotation of the coil form with respect to the base will vary the inductance of the coil carried on the form.

10. A device of the class described including a coliform having a wall and a radial flange, an inductance coil wound about the form, contacts carried by said radial flange, means electrically connecting the coil with the contacts, a base rotatably connected with the coil form, means connecting the coil form and base, a plunger housing mounted on the base beneath the flange, a plunger carried thereby and selectively engageable with the contacts, a spring normally urging the plunger into engagement with the contacts, and a prong carried by the base and having a lateral portion connected with the plunger housing, said coil form being relatively rotatable with respect to said base for selectively engaging the plunger with certain of the contacts and electrically connecting portions of the coil carried on the coil form. 1l. A device of thclass described including a coil form-having a wall'dening a lower por-A tion, a coil wound on the form, contacts carried by the coil form on said lower portion, means connecting the contacts with the coil, a base rotatably connected with the coil form, said base having a central portion and an outer portion dening a groove adapted to freely receive the lower portion of the coil form therein, means extending through the base at the central portion and through the wall for rotatably connecting said form and said base, a plunger housing carried by the base 'at the outer portion and disposed Yto confront the contacts, a plunger carried by the plunger housing and adapted for selectively engaging the contacts, Va prong carried by the base, said prong being adapted for removably mounting the device in a radio set, and a lead connecting the prong with the plunger housing, said coil form being rotatable with respect to the base for selectively connecting portions of inductance in thecircuit.

l2. A device of the class described including a coil form closed at its lower end by an end wall having an upwardly projecting boss, a coil wound upon the form, prongs carried by the coil form and projecting through the end wall, meanselectrically connecting the coil with the contacts, spring contact arms carried within the coil form and connected with the prongs, contacts carried by the coil form and adapted for engagement by said arms, a cam contact operating disk rotatable on the boss within the form and adaptable for selectively engaging the contact arms with the contacts whereby portions of inductance on the form may be electrically connected in a circuit, and means carried by the disk for rotating said disk.

13. A device of the class described including a coil form having a bottom wall, a coil Wound about the form, contacts carried by the coil form, means electrically connecting the coil with the contacts, prongs carried by the coil form and extending through the bottom wall, Contact arms vcarried within the coil form and connected with the prongs, the upper ends of said spring contact arms beingfad'apted to confront the contacts, a cam contact operating disk carried Within the coil form and having cam faces adapted for selectively engaging certain of the spring contact arms with certain of the contacts whereby inductance JOHN M. OBRIEN. [L S.] 

